Be self-controlled and alert.  Your enemy the devil prowls around like a roaring lion looking for someone to devour.  – 1 Peter 5:8
One of the things my drill sergeants advised me was to “stay alert, stay alive.”  During basic training, it did not really sink in very deep until I became more mature in my training.  Now that I am older, it is very clear to me what that means.  We need to be alert all around us.  We are aware of our surroundings when trouble lurks by, and we must do the same for our spiritual awareness.  Satan looks for unsuspecting victims to wound and destroy.  He wants to neutralize our strategy to advance the kingdom of God.  We need to be at the ready when the devil attacks.